Home>ASTM Standards>ASTM D2449-88(R2020) pdf free download

ASTM D2449-88(R2020) pdf free download

ASTM D2449-88(R2020) pdf free download.Standard Specification for Rubber Bales From Natural Sources—Limit on Coating
1. Scope
1.1 This specification covers bale coating on bales ofnatural rubber (that have rubber wrapper sheets on the bales) and includes test method description. It specifies the maximum permissible amount of such coating. 1.2 This specification is not applicable to natural rubber that is packaged with plastic wrappers, as no bale coating is used. 1.3 The following safety hazards caveat pertains only to the test method portion, Section 5, of this specification: This standard does not purport to address all ofthe safety concerns, ifany, associated with its use. It is the responsibility ofthe user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.4 This international standard was developed in accor- dance with internationally recognized principles on standard- ization established in the Decision on Principles for the Development of International Standards, Guides and Recom- mendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
4. Sampling
4.1 Carefully remove portions at random from the outside wrapper sheets from any three sides of the bale so as to lose a minimum of bale coating. Handle and store the sampled portions so as to lose a minimum of bale coating. The number ofbales sampled from a lot shall be in accordance with Practice D1485, or as agreed upon between the purchaser and the seller.
5. Test Methods
5.1 Summary ofMethods: 5.1.1 Method A—The amount of mineral filler from bale coating present on the outside wrapper sheets of the bales is determined using an ashing procedure. 5.1.2 Method B—The amount of bale coating on the outside wrapper sheets of all grades of smoked sheet rubbers only is determined by a brushing or scraping procedure. 5.1.3 The brushing or scraping procedure, while much faster, is not suitable for use on crepe sheet rubbers because of penetration through holes in the outside wrapper sheet and difficulties of removal from between wrapper sheets. This necessitates the use of the ash procedure on crepe sheet rubbers. 5.2 Significance and Use—The rubber bale coating is useful for eliminating the adhesion or sticking together of bales when in contact with each other during transportation and/or storage. Excessive coating may result in reduced compounded physical properties.5.3 Procedure: 5.3.1 Method A (Ash Method)—Die out or cut two 50 by 50-mm test specimens, within a tolerance of 61 mm, from each of three portions removed from the bale, taking care not to lose the bale coating. Test each specimen separately. Any bale coating falling from the test specimen should be added to the ash crucible together with the test specimen. Ash in accordance with Test Methods D1278, with the exception of the weight of the 50-mm square specimen to the nearest 0.01 g rather than a 5 to 6-g specimen of homogenized rubber. 5.3.2 Method B (Brushing or Scraping Method)—Die out or cut out a test specimen 150 by 150-mm, within a tolerance of 61 mm, from each of the three portions removed from the bale, following the precautions given in 4.1. Weigh the test specimen to the nearest 0.01 g before and after removal ofbale coating. Remove the bale coating, using a stiffwire brush or by scraping, taking care not to abrade rubber from the wrapper sheet while thoroughly removing as much of the bale coating as possible.

Maybe you like

Categories
Standards Tags